1976 xs650 by summertime?

It's summer time and I'm dinkin' around again with the bike. Had a quick question, is the sump oil filter cover the same across all years? Before I bought an actual lift for my bike I had used a scissor jack and.. well.. Used the bolt where you drain the oil from as my jacking point. Definitely a live and learn sort of thing. Anyhow, when the engine runs I get some slight leakage, whereas before this jacking snafu I had no problem. Thinking the best option would be to replace that panel.

Other than that, I've got drum brake pads on the way, a new rear brake light switch, and a throttle cable bracket. I need to shorten my throttle cable and looked up some vids, looks like I get to try my hand at some soldering. After that, need new pads on the front disc brake, master cylinder, then it's time to give it a test run! Just waitin on some dough for the master cylinder.
 
So I took my front caliper apart and the pistons are rusted into it. Any suggestions on removal? I assume the pistons themselves should be replaced if rusted, but what about the actual body of the caliper? Like could there be rust in the channels the brake fluid pumps through?

Secondly, I'm trying to figure which master cylinder to purchase from mikes, one of them specifically says single disc, but says 77 and later, whereas my bike is a 72 http://www.mikesxs.net/product/08-0255.html

Then there's another one that says for dual disc OR single disc, and has 72-76 listed. http://www.mikesxs.net/product/08-0265.html

What is the actual difference between these two products and which one should I go with? I'm getting dangerously close to getting this on the road, I rode to the end of my driveway and was totally thrilled to make it back to the garage in one piece. Guess I did my rear brakes fine, the brake light switch I installed even works correctly!
 
I use compressed air to blow out stuck caliper pistons. You need to break them free first though. Get a large C-clamp and squeeze each piston back into the bore a bit to free it up. Then apply the compressed air. It may only move out a little and you'll need to C-clamp it back in again. Keep at it, blowing out, clamping back in, and eventually, they'll come out.

On your early caliper, both pistons move. On the later calipers, there is only one piston. That's why there are two different sized MCs. You want the 2nd one with the larger 16mm bore. You need to pump more fluid because you're moving two pistons. So, it's not so much a single or double disc but rather how many pistons you need to move. That 16mm MC would be fine for two later calipers because you're moving a total of only two pistons.

But, all these stock size offerings are a trade-off. Here's a chart with MC to piston size ratios for you to study. The pertinent info you'll need is that your early MC had a 5/8" bore and your calipers have 48mm diameter pistons. The later single piston caliper has a 38mm diameter piston and usually had a MC with a 14mm bore. From the recommendations given, you'll see that you may actually want to use the later 13mm or 14mm bore MC to get a better ratio .....

http://www.vintagebrake.com/mastercylinder.htm
 
Thanks for the tip with the c clamp 5twins, worked great. They look to be in pretty good condition!
 

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Yes, those look to be in fine shape. Keep in mind that once assembled and pressurized, the pistons move very little. The only area on them that needs to be in good shape is the small portion that would move in and out on the seal. They can be all pitted up elsewhere.
 
So is there any reason why a generic air filter such as http://www.ebay.com/itm/52MM-Clamp-...Parts_Accessories&hash=item2c626d4984&vxp=mtr wouldn't work with my ride? I typically order stuff from mikesxs but even their blemished filters are $8.50 each. Also, any reason why a generic throttle tube in 7/8 would be an issue? I went into a local dealer and the person at the desk said, "well if you care about safety at all then you'll order the right part for the bike." I say, "ok how much?" "21.50."

Needless to say I said screw that, politely, and now I'm just curious about the interchangeability of parts in general. Like there's a throttle tube and it doesn't have xs2 listed, but the bars are 7/8 so what does it matter.. right?
 
Stay away from K&N style pleated pods, especially the cheapo ones like that eBay offering. They don't work well on our CV carbs. They don't flow the air smoothly and that mucks up the slide lift. If you want to run pods, get the UNI foam ones. They work correctly.

If you're looking for just the plastic throttle tube to fit into the original housing then you probably would need an original tube. If you're talking about the complete assembly, tube and housing, then any should work, as long as the original cable or cables will fit it.
 
Quick little update, I ended up lookin a bit closer and reading other threads on here about throttle sticking. One of them had just some simple advice, start at the carb and work your way up, one thing at a time. Well I ended up getting to the tube itself and while sliding it around on the bar I noticed some areas it was totally smooth, others were making it hang up. Felt around the bar a bit by hand and could feel it wasn't 100% smooth. Took a few different grades of sandpaper to the bar and spent about 10 minutes or so on it. It got better and better until finally it had no resistance, hooked up the housing and the cable, adjusted it, and now it works perfectly!

That may sound pretty rudimentary to some of you skilled folks, but that was a big victory for me. Saved some money in the process too. Next up, fork oil and putting the front brakes back together.
 
So I have a very basic question, how are the brake pads held into the caliper? I got new ones.. With tabs on them (different from what I pulled off).. but they sit totally loose in the caliper. I thought I read somewhere on here that the pads rest against the rotor permanently and that's just how it is. When I took them off the bike and out of the caliper it felt like they kind of snapped out, granted they'd been in the thing sitting for 20+ years.
 
Hello again forum goers! So I clearly don't have the bike on the road yet, I'm at some very basic humps I'm having difficulty getting over.

First off, pod filters. I ordered some last summer and they were way too long for the bike, my fault for not reading or at the very least measuring. Earlier in this thread 5twins suggested to me to use uni pod foam filters. I BELIEVE my carb is a bs38, judging by the jets, and the appearance. I do not have the airbox, it wasn't with the bike when I got it. Would these filters work well with them or would the holes be blocked? http://www.amazon.com/Uni-Pod-Filte...357&sr=8-1-fkmr1&keywords=uni+pod+filter+54mm

What do you guys use on your bs38s? Has anything worked better rather than not?

Secondly, I still have a question about how my front disc brakes work. I have been looking up youtube videos and reading what I can find but these particular brakes seem to not really be well documented? So the caliper has two circular pads, each with a short tab, 5/16". There is no screw, clip, or anything else that actually holds them in place that I have found. Do the pads literally just rest against the rotor the entire time the bike is in motion? Is that how most disc brakes function? This is new territory for me and I'd like to get the brakes right for obvious reasons.

Thanks again for all the help up to this point, it is greatly appreciated. I am nearly done with the bike, at least the obvious stuff. Front brake, filters, I need a new pad for my seat because the old one is corroded, then it'll all be ready for a test drive.

-Lynden-
 
For BS38s, you want a filter with a smaller 2" I.D. mounting flange. That would be the PK-82 in those short filters, but I don't recommend them as they don't flow as much air as these longer versions .....

Uni-CheckValve.jpg


These are the 2"x4" UP4200. The 2" flange fits the BS38s like a glove and the 4" length is the longest you can squeeze in front of the battery box.

http://www.amazon.com/Uni-Filter-UP...TF8&qid=1429562635&sr=1-1&keywords=UNI+up4200
 
@Airwolfie That is an incredible resource, thank you for sharing that. It is far more detailed than my manual. Makes me want to bring a pc out to the garage for quick access, the iPad will do though!

@5twins Thank you for the swift reply. Would using the side panels along with these pods restrict airflow?
 
I don't think having the side covers on restricts the air flow much. Most everyone who runs the pods on a near stock bike does so with the side covers in place. I use the covers, they were just removed for this photo. It also illustrates what to do with the breather hoses. Many of us install a power brake check valve in the end, about $5 each at the auto parts store. This is a one-way valve that lets pressure out but not back in. It fits perfectly into the end of the stock breather hoses and poised over the pod as shown, any oil that may drip out is simply absorbed and recycled through the pod.

PowerBrakeCheckValve.jpg
 
Anyone have solutions for replacement brackets that hold the brake line from master cylinder to caliper? I think there's supposed to be two that help lead the line down the forks.
 
One solution.
Found at most hardware, auto stores, sometimes known as an Adel clamp.

adel_clamps-1.jpg


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brake detail.jpg
 

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Cool idea Gary. I got the bike rolling for the first time since '92, according to the old tabs on it anyway. Took it around the block twice and it sounds nice. I noticed after doing the brakes the lever is super firm to pull, with hardly any wiggle room. Will it loosen over time or would ejecting some fluid from the caliper help?

Second thing that jumped out at me is while idling, if I Rev up it hangs for about 3-5 seconds or so. While riding I didn't notice it so much, but it was a short ride and it's been ten years or so for me. It did pop a bit while in gear coming down in rpms after accelerating. Air leak somewhere maybe?
 
Certainly sounds like it's running lean. Air leaks or blocked pilot jets I expect.


VVLynden said:
Cool idea Gary. I got the bike rolling for the first time since '92, according to the old tabs on it anyway. Took it around the block twice and it sounds nice. I noticed after doing the brakes the lever is super firm to pull, with hardly any wiggle room. Will it loosen over time or would ejecting some fluid from the caliper help?

Second thing that jumped out at me is while idling, if I Rev up it hangs for about 3-5 seconds or so. While riding I didn't notice it so much, but it was a short ride and it's been ten years or so for me. It did pop a bit while in gear coming down in rpms after accelerating. Air leak somewhere maybe?
Click to expand...
 

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